Control mechanism for two motion flat-type switches



Jan. 20, 1959 H. SENGEBUSCH CONTROL MECHANISM FOR TWO MOTION FLAT-TYPE SWITCHES 3 Sheets-Sheet 1 Filed Dec. 17, 1953 INVENTOR BY HANS SENGEBJSCH ATTY.

Jan- 1959 H. SENGEBUSCH 2,870,262

CONTROL MECHANISM FOR TWO MOTION FLAT-TYPE SWITCHES Filed Dec. 17, 1953 3 Sheets-Sheet 2 INVENTOR HANS SENGEBUSCH ATT Y.

Jan. 20, 1959 H. SENGEBUSCH CONTROL MECHANISM FOR TWO MOTION FLAT-TYPE SWITCHES Filed Dec. 17, 1953 5 Sheets-Sheet 3 INVENTOR HANS SENGEBUSCH BY A ATTY.

MECHANISM FOR TWO MOTION FLAT-TYPE SWITCHES Application December 17, 1953, Serial No. 398,755

16 Claims. (Cl. 1797-2752) Contract.

The present invention relates in general to improvements in selective switches for use in telephone systems. More particularly this invention relates to improvements in drive mechanisms for two motion flat type selective switches.

It is the principal object of this invention to provide an improved motor drive for flat type switches capable of controlling the operation of switch wipers in both a rotary and a radial direction.

Another object of this invention is to provide a motor drive mechanism for a two motion selective switch capable of a step-by-step operation in response to controlling dial pulses and an uninterrupted continuous operation when the switch is hunting an idle trunk.

A further object of this invention is to provide a motor drive mechanism capable of continuous reverse operation to restore the switch wipers to their normal position.

Still another object of this invention is the provision of an improved drive mechanism capable of driving the switch wipers with an uninterrupted continuous motion at a rate equivalent to the step-by-step operation of 80 to 100 steps per second when the switch is hunting an idle trunk and capable at the same time of positively arresting this motion when an idle trunk is found.

An important feature of this invention is a novel arresting mechanism arranged to either accomplish a stepby-step operation of the switch or the positive interruption of a continuous hunting action of the switch.

Another feature of this invention is the use of only four wipers in conjunction with a 200 point switch where eight such wipers have previously been required, made possible by the rapid and positive operation of the new drive mechanism.

Additional objects and features of this invention will become apparent from a consideration of the description and claims which follow.

The invention, both with respect to its organization and to its operation can best be understood by reference to the description taken in conjunction with the accompanying drawings of which:

Figure 1 is a detailed plan view showing a broken section of a switch bank together with the contact end of the switch wipers;

Figure 2 is a plan view showing the motor drive and arresting mechanism together with the wipers and wiper carriage and associated locking mechanism;

Figure 3 is a broken perspective view showing the relation of the details of the motor drive and arresting mechanism;

Figure 4 is a detailed plan view showing the drive motor interrupter mechanism; and

Figure 5 is a diagrammatic view showing the motor magnet energizing circuits and the interrupter mechanism controlling the circuits together with the relative position of the armature and the interrupter rotor at a given instant of rotation.

A two motion selective switch operated by a motor United States Patent 2,870,262 Patented Jan. 20, 1959 drive and control mechanism according to the disclosure herein is capable of performing any of the Well known functions of two motion switches such as telephone system linefinders, selectors or connectors, including the selection of any one of a plurality of groups of conductors. The switch control mechanism as embodied in the present invention is adapted to operate in conjunction with the switch wiper positioning elements and locking assembly disclosed in the application of Hans Sengebusch, now Patent 2,780,675, issued February 5, 1957-. Since these elements and assembly have been described in detail with respect to operation and construction in that application they will be described herein only to the extent necessary to describe the present invention.

in a two motion selective switch embodying the drive motor and control mechanism constructed in accordance with the present invention, switch wipers as shown in Fig. 1, slidably mounted on a rotatable carriage, are adapted to be moved radially along the carriage with respect to its center of rotation. The wipers are adapted to engage a wire bank of the self-multiplying type, the particular bank used with the present invention providing for 200 station points. In a wire bank of the type described the sets of conductors are extended vertically to perpendicularly intersect a plane in arcs of concentric circles whose centers coincide with the center of rotation of the switch Wipers. The sets of conductors are grouped radially by means of it) radially disposed bank strips 91 mounted on a frame 92 the conductor sets being imbedded in the bank strips thereby presenting bare wire contact points to radially moving switch wipers. The circularly disposed wire bank is divided into two concentric groups of 190 station points each, the first group composing the first 10 sets of conductors in the radial groups, the second 100 group composing the remaining sets of conductors in the radial groups. Each radial group will therefore include at least 20 sets of conductors. Thus, after the switch wipers have been positioned before any one of the 10 radial groups of bank strips desired, the wipers may be further moved into contact with any one of the 20 sets of conductors. While this embodiment of the invention discloses the adaptation of this switch for use with a 200 point wire bank, it is to be understood that this invention could readily be adapted for use with any reasonable number of lines.

As shown in Fig. 2, the carriage 66 supporting the wipers is rotatably mounted on a common shaft with a rotary driving element 70 similarly mounted. A radial lock bar 73, hinged to carriage 66 and operated by locking magnet 10 to engage the notched positioning plate 15, is provided to lock the carriage 66 to the driving element 70. Through the operation of lock bar 73 the carriage 66 is either locked to driving element 70 and is free to rotate with that element or the carriage 66 is locked from rotation in any one of 10 angular positions corresponding to the angular placement of the bank strips hit as determined by the particular notch of positioning plate 15 engaged by the radial lock bar 73. In either case driving element 76 is free to rotate. The radial movement of the wiper is accomplished by means of a gear 72 mounted on the carriage 66 and engageable with the gear teeth 71 on a portion of the periphery of the driving element '70 and with teeth on a slidable rack 67 to which the wipers are ultimately attached. Thus when the carriage 66 is locked against rotation the driving element 70 rotates the gear 72 which in turn imparts centripetal movement to the wiper rack 67, the direction depending upon the direction of rotation of the driving element 7 0.

The drive motor 4% and arresting mechanism 50 control the rotation of the driving element 70 by means of a pinion gear 20 engageable with the gear teeth 71 of eeroeaa the driving element 70 as shown in Fig. 3. The motor 40 is of the reversible type having a rotary armature 21 rigidly mounted on the same shaft 24 with pinion 20. In the motor 40 the armature 21 is successively influenced by three electromagnets 41, 42, and 43 to rotate continuously. As shown in Fig. 5 the energizing circuits of the electromagnets are controlled by an interrupter mechanism 100 operated by the shaft 24. A rotor 109 rigidly mounted on the shaft 24 is provided with lobes 110 which when rotated when the armature rotates causes the successive closing of the spring contacts 102, 103, and 104. Thus, for example, it can be seen from Fig. 5, that, as the contacts 102 are closed, the circuit to the magnet 43 will be closed and the electromagnet 43 will influence a leg of the armature. Reversal of the armature is accomplished by a partial rotation in the position of the springs 102, 103, and 104 thereby reversing the order in which the circuits of the electromagnets 41, 42, and 43 are closed. The armature 21 is then caused to rotate in the reverse direction through the reversal of the order of influence of the electromagnets. The rotation of the armature 21 and the pinion uninterruptedly rotates the driving element 70 to rotate the carriage 66 and move the wipers radially. For step-bystep operation in response to dial pulses the arresting mechanism 50 by means of a pair of arresting dogs 34 and in alternate engagement with an arresting star wheel 25 also rigidly mounted on the shaft 24 etfects an interrupted rotation of the driving element 70, each partial rotation moving the wipers an angular distance equal to that of the distance between bank strips 91 or the radial distance equal to that of the distance between each set of conductors on the bank strips 91. For either step-by-step or continuous operation the wipers are checked from their rotary movement by the operation of the radial lock bar 73 at which time the rotary motion imparted by the driving element 70 is translated into radial motion by action of the gear 72. Restoration of the wipers to their normal position is effected by the reversal of motor 40. Lock bar 73 remains engaged with the positioning plate 15 until the wipers have been fully withdrawn from the bank strips 91 at which time the locking magnet 10 actuates to release the lock bar 73 and permit carriage 66 to completely restore the wipers. The preferred embodiment of the present invention can best be described in detail by reference to Figs. 2 to 5 of the accompanying drawings. The various components of the invention are mounted on a base 96 which base is adapted to be stacked vertically with other switches of the type herein described. The rotary driving element 70 and the rotatable carriage 66 carrying the Wiper rack 67 and wipers described in detail in the previously cited Sengebusch patent, are mounted freely rotatable on a common shaft 65 rigidly fixed to base 90 in any convenient manner known in the art. To operate the carriage locking means the magnet 10 is provided together with its armature element 11 and the positioning plate 15 all mounted on base 90 in any well known manner. A pair of stops 81 also mounted on the base 90 are provided to limit the rotation of the carriage 66.

The rotation of the driving element 70 is controlled by the drive motor in cooperation with the arresting mechanism as most clearly shown in Fig. 3. The drive motor 40 comprises three electromagnets 41, 42 and 43 mounted on base 90 in any convenient manner by means of'a single heel-piece 48 together with their respective pole-pieces 44, 45 and 46 and is operated in a manner hereinafter to be described. In addition, motor 40 includes a four leg armature 21 rigidly secured on a shaft 24 which shaft is rotatably mounted on base 90 by any convenient means. The armature 21 is disposed to rotate in the same plane as the pole-pieces 44, 45 and 46. The pole-pieces 44, 45 and 46 are so arranged that a perpendicular pole-face 47 of one of these pole-pieces is presented to the legs of the armature 21 at intervals of 120". A bridge 23, secured to pole-pieces 44 and 46 of electromagnets 41 and 43, respectively, by mounting means 27, is provided to maintain the operative relationship of the shaft 24 and, thereby, the armature 21, with the po1e-pieces 44 and 46. Also rigidly secured on the shaft 24 with the armature 21 is the pinion gear 20 the teeth of which engage the teeth 71 in the periphery of the driving element 70. Thus as the armature 21 is caused to rotate through the operation of the electromagnets 41, 42 and 43 the pinion 20 will also rotate, which rotation is transmitted to the driving element 70 through the engagement of the gear teeth 71 and the pinion 20.

The rotation of the pinion 2t? and thereby the driving element 70 is controlled by the operation of an arresting mechanism 5%. Two control relays 51 and 52 mounted on base by mounting means 55 are provided as actuating means. The armature 56 of relay 52 is pivotally mounted on heel-piece 53 by means of pivot pin 86 and clamping means 58 and 61 and is provided with an armature lever 56a. The armature 56 is biased in a counter-clockwise direction and the lever 56a held against a stop '76 on the heel-piece 53 by a spring St the tension of which may be adjusted by mounting means 88. A non-magnetic disc 89 fixed to the armature 56, in addition to the spring 30, insures the instant release of the armature 5'6 upon deenergization of the magnet 5'2. On the single heel-piece 48 of motor magnets 41, 42 and 43 is pivotally mounted by means of a pivot pin 32, a rocker 33 having an arm 33a engageable with the extremity of the lever 56a of the armature 56. Thus the rocker 33 can be made to pivot in a counter-clockwise direction about pin 32 as the engaging armature lever 56a is caused to rotate in a clockwise direction by the actuation of the armature 56 as shown in Fig. 2. The rocker arm 33a is biased toward the armature lever 561/ by means of a spring 36 extended between a lug 33b on one extremity of the rocker 33 and an extension 5311 of the heel-piece 53. A pivot pin 37, its axis parallel to the axis of pin 32, is securely fixed toward each extremity of rocker 33. Pivotally mounted on the pins 37 is a pair of parallel arresting dogs 34 and 35 having their tips inwardly disposed in a parallel relationship and so arranged that a reciprocal motion is imparted to the dogs by the movement of rocker 33 about the pivot pin 32. The pivoted end of arresting dog 35 is provided with a slot 33 in which the pin 37 can be freely moved with the result that the arresting dog 35 may be pre vented from following the movement of the rocker 33. A bias spring 39 attached to extension 35:; of dog 35 and the rocker 33 holds one end of the slot 38 against the pin 37 for normal movement of the arresting dog 35 by the rocker 33.

The arresting dogs 34 and 35 are adapted to engage the prongs of a four prong star wheel 25 rigidly mounted on the shaft 24- and separated from the armature 21 by a bushing 32. A slot 49 of the recess 22 opened in a turned-down portion of the bridge 23 serves as a support for the arresting dogs 34 and 35 and at the same time limits their lateral movement. When either of the arresting dogs 34 and 35 are engaged with the star wheel 25 the armature 21 and hence the pinion 26 and the driving element 74 are prevented from rotating. Assuming a normal position of the arresting mechanism. i. e., the arresting dog 34 in engagement with the star wheel 25, energization of the relay 52 causes the armature lever 56a to engage the rocker arm 33:! with the result that the rocker 33 is pivoted in a counter--clocltwise direction about the pin 32 as seen in Fig. 2. The arresting dog 34 is thereby withdrawn from engagement with a prong of the star wheel 25 and, assuming a clockwise torque applied by the drive motor 4%, the star Wheel 25 and hence the pinion gear 20 is free to rotate in a clockwise direction. The drive element can therefore be rotated in a counter-clockwise direction.

However, the arresting dogs 34 and 35 are so arranged that before the dog 34 is fully withdrawn from engagement with a particular prong of the star wheel 25 the dog 35 is forced onto the sloping shoulder of the engaged prong into a position directly in the path of rotation of the next following prong. Thus, since the star wheel 25 is provided with four prongs, the star wheel 25 and hence all the elements mounted with it on the shaft 24 are permitted to make approximately one quarter revolution for each energization of the relay 52. A full one quarter revolution is not possible at this point due to the interposition of the tip of the arrestingdog 35. When the relay 52 is tie-energized and the armature lever 6a and the rocker 33 are restored the dog 35 is withdrawn from engagement with the prong of the star wheel 25 and the latter is again free to rotate. But in a similar manner as before, the dog 35 is not fully withdrawn until the dog 34 has taken a position in the path of the prong engaged. Then, as the dog 35 is completely withdrawn, the star wheel 25 is permitted to complete the full quarter revolution. The double bank strips 91 shown inFig. l have been so arranged that as the star wheel 25 and its associated pinion gear make a full quarter revolution the driving element 70 is caused to move the wipers through an angle equal to the angular separation of the double bank strips 9.1. Should the carriage 66 be locked against further rotation one full quarter revolution of pinion gear 20 will cause the driving element '70 to move the wipers radially a distance equal to the radial distance between each set of conductors on the bank strips 91.

To insure the positive operation of the arresting dogs 34 and 35, engagement with the prongs of the star wheel has been facilitated by undercutting the contact surfaces of these elements, thus, as shown in Fig. 2, arresti ing dog is easily thrust onto the guiding slope of the prong of the star wheel 25 engaged by the dog 34 as the latter is being withdrawn. A fixed spring 23 secured to heel-piece extension 53a by mounting means 94 is provided to absorb the shock of abruptly arresting the rotating star wheel 25. This shock is transmitted from the arresting dogs 34 and 35 to the spring 93 by means of an element 5 5 slidably mounted on the turned-down portion of the bridge .3 by mounting means 95.

To permit the star wheel 25 to rotate freely uninterrupted by either of the arresting dogs 34 and 35, means are provided to restrain the dog 35 from the longitudinal movement ordinarily imparted by the partial counter-clockwise rotation of the rocker 33 about the pin 32. A projection 57!) of the armature lever 52%: of e the magnet 51 is engageable with a similar proiection 35b of the extension 35:: of the arresting dog 35. Thus, if the relay 51 is energized an instant before the relay 52 is energized, the armature 57 will be caused to rotate counter-clockwise and the projection 57!; will eni gage the projection 35]) thereby effectively restraining the dog 35 from longitudinal movement. Should the relay 52 now be energized, the rocker 33 is free to rotate about the pin 32 against the spring 39 since the slot 325 permits the pin 37 to move freely with respect to the dog 35. A spring 97 connected between a lug on the end of the armature lever 57a and a stud pin 23 mounted on one side of the heel-piece 53 insures the instant release of the arresting dog 35 upon de-energization of the reiay 51 and maintains the armature lever 52a against a stop 99 of the heel-piece 53 when the relay 51 is not in operation. From the foregoing it is evident that if the relays 5i and 5'2 are successively energized in that order and are maintained energized both of the arresting dogs 34 and 35 will be withdrawn from engagement with the star wheel 25 and the shaft 24 together with the elements mounted thereon will be free to rotate in either direction until either the relay 51 or 52 is Clo-energized. As it will be seen hereinafter, two operations of the switch require that the shaft 24 with its elements be capable of free, unimpeded rotation: the continuous searching for an idle trunk when the switch is employed as a linefinder and the restoration of the switch when employed in any capacity.

The restoration of the switch to its unoperated position is accomplished in this embodiment of the invention by reversing the direction of rotation of the armature 21 of the drive motor in the manner to be described. However, a description of the reverse operation of the drive motor 40 should properly be preceded by an explanation of its forward operation. As described hereinbefore and shown in Figs. 3, 4, and 5, the armature 21 is disposed to rotate with the shaft 24 in a manner such that each of the legs of the armature 21 are successively moved past the face 47 of each of the polepieces 44, and 46. Assuming the instant position of the armature 21 with respect to the pole-pieees as shown in Fig. 5, that is, the armature 21 having one of its four legs approaching the face 47 of the pole-piece 45, it will be seen that if now only the electromagnet 42 of the magnets 41, 42, and 43 is energized the pole-piece 45 of the magnet 42 will attract the armature leg closest to it. Since the pole-pieces are disposed 120 apart Whereas the armature legs are separated by the nearest leg will be less than 3'0 distant in either direction from the closest tractive surface of the pole-piece 45 as viewed in Fig. 5. Assuming then the rotational position of the armature 21 as shown, it will therefore be caused to move in a clockwise direction until this leg is in a position directly opposite the face 47 of the polepiece 45 where the attractive force will be strongest. if at this moment magnet 42 is de-energized and the magnet 43 is energized the armature 21 will be further caused to rotate another 30 in a manner identical to the preceding. Similarly, upon the de-energization of the magnet 43 and the energization of the magnet 41, the armature 21 will rotate a further 30. Thus as each magnet of the magnets 41, 42, and 43 is successively energized and de-energized in that order the armature 21 is caused to rotate in a clockwise direction.

The reversal of the motor, causing the armature to be rotated in a counter-clockwise direction in a manner similar to that for rotation in a clockwise direction, is accomplished as described in the following. Referring again to Fig. 5 and assuming the instant position of the armature 21 with respect to the pole-pieces as shown, if only the magnet 41 were to be energized instead of the magnet 42 as was the case above, on the same principle armature 21 will be caused to rotate in a counterclockwise direction. Similarly, the armature 21 will continue to rotate in a counter-clockwise direction as the magnet 43 andthe magnet 42 are successively energized and de-energized. Clearly then, as the magnets 41, 43 and 42 are successively energized and tie-energized in that order the armature 21 will be caused to rotate in a counter-clockwise direction.

The magnets 41, 42 and 43 are electrically connected to any source of power, not shown, in any manner well known in the art. To effect the successive interruption of the respective circuits for the successive energization and de-energization of the magnets 41, 42 and 43 in the operation of the drive motor 40 and to reverse the sequence of the successive interruption to reverse the drive motor 40 an interrupting mechanism is provided. A suitable disk 101 mounted freely rotatable on the shaft 24 serves as a convenient mounting base for 3 pairs of contact springs 102, 1013 and 104 as shown in Figs. 3 and 4. Each of the pairs of springs 102, 103 and 104 are radially disposed with respect to the center of the shaft 24 and are separated by an angle of The springs are mounted on the disk 101 by any convenient insulating means a and are electrically connected in the proper circuits of the magnets 41, 42 and 43 by means of suitable terminals on each spring as shown in Figs; 3 and 4. The contact springs 102, 103 and 104 may he employed in any convenient manner to establish the circuit connections. in the preferred embodiment of the invention a four lobe cam 109 of a suitable insulating material securely carried on, and rotatable with, the shaft 24 is provided to actuate the pairs of contact springs 192:, 1633 and 104. As the cam 109 is rotated by the shaft 24 its lobes 110 are adapted to be sucessively moved between the outwardly turned faces of each pair of springs thereby successively opening a normally closed pair of contacts 106 in each spring. As a lobe 11d of the cam 109 passes from contact with a spring the circuit to the magnet associated with that spring is closed and the magnet is energized. The lobes 110 are so constructed and arranged that no more than two of the lobes will be in contact with two pairs of springs at any one time, that is, at least one pair of springs will always be closed. Assuming the position of the cam 109 and its lobes 11th with respect to the pairs of springs 102, 103, and we as shown in Fig. 4, and assuming further that the springs 102 control the circuit of the magnet 42, it is readily seen that contacts 1% of the springs 192 will be closed and therefore the magnet 42 will be energized. This is in accord with the position of the armature 21 as shown in Fig. 5, where, at the instant, one leg is approaching the face 47 of the pole-piece 45 of the instantly energized magnet if the springs 1G3 and 194 now control the circuits of the magnets G3 and 41, respectively, it is further evident from Fig. 4 that, if the cam 109 continues its clockwise rotation, a lobe 115;

of the cam 1199 will open the contacts we of the springs v 192 while at the same time another lobe 119 will pass from contact with the springs M3 thereby closing the contacts 1% in the circuit of the magnet 43. During this increment of rotation the lobe 110 in contact with the springs will not have moved a suflicient distance to pass from contact with the spring and the circuit to the magnet 41 will remain open. magnets 41, 42 and 43 is successively energized and deenergized in a clockwise direction as the lobes 116 of the cam 109 successively open and close the contacts associated with the magnets.

The reversal of the armature 21 is accomplished by rotating the position of the contact springs 1112, 1.03 and 104 through an angle of approximately in a clockwise direction as viewed in Fig. 4 until the projection 107 meets the stop 108. As the position of the springs is thus rotated it will be seen from the position of the cam lobes 110, assuming their position as shown in Figs. 4 and 5, that the contacts 106 of the springs 1&2 and 103, and therefore the circuits of magnets 42 and 33, respectively, will be opened. The spring 164, however, will have moved from contact with a cam lobe 110 and the contacts 1% of the spring 1% will be closed. The magnet 41 will be energized and the pole-piece 44 will attract the leg of the armature 21 it. Assuming as in the description of the clockwise operation of the drive motor 40, the position of the armature legs as shown in Fig. 5, it can readily be seen that the attraction of the pole-piece 54- will cause the armature 21 to rotate counter-clockwise. The further operation of the elements of the drive motor for the continued counter-clockwise rotation is identical to that described above for clockwise rotation.

T o initiate and maintain a continuous rotation of the armature 21 the position of the lobes 11d of the cam 109 are so adjusted with respect to the position of the legs of the armature 21 that the magnet energized will be de-encrgized a brief interval before an armature leg is directly opposite the face of its pole-piece and, further, that the next succeeding magnet will be energized an instant before the former magnet is ale-energized. An additional adjustment of the position of the lobes 110 of the cam 199 in the same direction is necessary to provide time for the magnet energized to build up an adequate field for its pole-piece.

in closest proximity to Thus each of the The contact springs 102, .103 and 104 are rotated through their limited arc, and thereby the reversal of the drive motor 4% 'is controlled, by a control bar 66 similar in operation and construction to the control bar disclosed in the Sengebusch application referred to hereinbefore. The control bar all which is operated by the co-operative action of the driving element 7% and the carriage 66 locking mechanism is pivotaily connected on one end to 21v lever arm til by pivot means and is adapted for longitudinal movement. The lever arm iii which is pivotally mounted at one end on the base 9% by pivot means 112 is providedat the other end with a longitudinal slot by means of which the lever arm 112 is engageable with a pin M4 securely carried on the disk 1G1 as shown in Fig. 4. Thus, as the control bar 64) is given longitudinal movement, the lever arm 111 will be caused to pivot about the means 112 and the disk lllll will be rotated by the action of the slotted end of the arm 111 against the pin 114 of the disk .191. To limit the amount of rotation of the disk 101 and, therefore, of the contact springs 192, 193 and 104 mounted thereon, to the amount required to change the direction of rotation of the armature 21, a pair of lugs on the disk 101 is provided which check further rotation when either is brought up against a stop post 198 fixed on the base i i). The lever arm 1311 is biased in a clockwise direction by a spring 115 extended between a lug on the arm 111 and retaining means 117 on the base 90. The action of the spring 1E5 maintains a stop lug 1d! of the disk 1M held against the stop post 108 thus holding the springs 1&2, 103 and 104% in a normal position, that is, in a position to initiate or maintain a clockwise rotation of the armature 21, as shown in Figs. 4 and 5.

The control bar 66 is adapted at its other end for cooperation with a lever 17, a lever 82 and a post 64 of the driving element 75 The control bar 69 is moved longitudinally by the action of the lever 17 an arm of which is engageable with a notch 60b of the control bar. The lever 17 in turn is operated by the armature element 11 of the magnet 10 such that when the magnet iii is error gized the control bar 60 will be moved longitudinally against the biasing action of the spring 116. The post 64 securely mounted on the driving element 7% is engageable with a projection 60a of the control bar 66 as the driving element 76 is rotated to its fully restored position as shown in Fig. 2, thus moving and holding the control bar and its notch 6% out of engagement with the lever 17. The control bar 69 can not now be moved and therefore the disk 1G1 and the springs 1e71, 1&3 and 164 can not be rotated to cause reversal of the motor until the operation of the switch has moved the post 64 from contact with the projection dlla thus permitting the notch 60/) to once again engage the lever 17. To force the engagement of the notch sea with the lever 17 the lever 32 pivotally mounted on the base l t is provided. Through the action of a spring $3 the lever 82 biases the control bar so in a counter-clockwise direction as viewed in Fig. 2 against the arm of the lever 17 and also, by engaging the notch 60c, holds the control bar in its operated position during the restoring operation. A guide post 63 fixed to the base 91) is provided to limit lateral movement of the control bar 64 The restoration of the switch after its operation is accomplished by the energization of the magnet 1d the armature element .11 of which operates to cause the lever 17, by means of its arm engaged in the slot 60b, to move the control bar 64 against the spring 116. As the arm 111. is pivoted counter-clockwise by the control bar 6% the contact springs 102, M 3, and the are turned to their reversing position and the drive motor 49 rotates the drive element 70 back to its normal position.

Since the function of each element of the invention has already been described in detail the general operation of the switch need be considered only briefly. Initially the drive motor places a clockwise torque on the shaft 24 when the switch is taken into use. Simultaneously the amass 9v magnet 10 is energized thereby moving the arcuate shaped portion of the armature element 11 away from its contact with the tip 73a of the lock bar 73 thereby permitting the tip 73a to clear the notches of the positioning element 15 as the carriage .66 is rotated. It will be recalled that at this point the lever 17 does not operate to reverse the movement since the slot 6% of the control bar 60 has been pushed out of engagement by the action of the post 64 on the driving element 70. At this point also the carriage 66 and the driving element 70 are locked together preparatory to the rotational movement of the wipers 118. The magnet 52 is now energized and deenergized a number of times corresponding to the radial group of conductors to be selected. As the armature 56 is actuated the rocker 33 alternately introduces and withdraws the arresting dogs 34 and 35 from contact with the prongs of the star wheel 25. The first energization and de-energization of the magnet 52 permits the star wheel 25 and therefore the pinion to make one quarter revolution with the result that the driving element 91) and therefore the carriage 66 with its wipers 118 are caused to rotate one rotary step. 'The interruption of the star wheel is continued in the manner described above until the wipers 118 have reached a position before the selected radial group of bank strips 91. At this point the magnet 10 is deenergized and the tip 73a of the lock bar 73 is forced into one of the notches of the positioning element 15 by the restoring armature element 11. The lever 17 is returned to normal and, since the control bar 6i) is no longer restrained by the post 54 of the driving element 70, the lever 82 forces the notch into engagement with the lever 17. The control bar 61) is now in the position to control the reversing mechanism when the magnet 10 is again energized. Movement of the tip 73a of the lock bar 73 into one of the aforementioned notches locking the carriage 66 from further'rotation, at the same time unlocks the carriage from the driving element 70 which is then free to be rotated further by the drive motor 40. To indicate the particular radial group of bank strips before which the switch wipers 113 have come to rest, an indicator scale 78 mounted in any convenient manner to the base has been provided. A pair of fingers 77 on the carriage 66 oppositely disposed from the wipers 118 are adapted to bracket any one of a series of numerals ap pearing on the scale 73 corresponding to the particular radial group of bank strips selected and to which the wipers 118 have been rotated. Further rotation of the driving element 7% will be transmitted to the gear 72 carried on the carriage 65. This rotary movement will in turn be translated into a radial movement of the switch wipers 118 by means of the rack 67 slidably mounted on the carriage 66 and in engagement with the gear 72. The driving element 70 is now rotated further in the same manner as for the first series of dial pulses, the magnet 52 being energized and de-energized a number of times corresponding to the set of conductors on the bank strips between which a connection is to be established.

At least two operations of the switch require the continuous, uninterrupted movement of the switch wipers 118. Since the second group of lines is located directly outside of the first 100 group, the bank strips of the second group being radially disposed following those of the first group, it is necessary when dialing into the second group that the wipers move rapidly and smoothly through the first group before responding to the next series of dial pulses. Such uninterrupted movement is also necessary when the switch is hunting an idle trunk as is the case when the switch is utilized as a selector.

When the switch wipers are to be given uninterrupted movement the magnet 51 is energized before the star wheel 25 is freed for further rotation by the action of the magnet 52 with the result that the armature lever 57a is moved in a-counter-clockwise direction about the pivot pin 87 against the biasing spring 97. The projection 57!) is brought into the path of the projection 35b of the arrest- 10 ing dog extension 35a thereby restraining the arresting dog 35 from any longitudinal movement. If the magnet 52 is now energized the arresting dog 34 will be withdrawn from contact with the particular prong of the star wheel 25 engaged as previously described. The drive motor d0 now rotates the driving element uninterruptedly until the switch wipers 13 have reached the radial position in the bank strip selected. This position will either be an idle trunk or the position in the second 100 group at which further penetration will be accomplished in response to the next series of dial pulses. At this point the magnet 52 will be de-energized and the arresting dog 34 will be forced by the action of the rocker 33 into the path of rotation of the prongs of the star wheel 25. Further stepping as previously described can now be accomplished in response to dial pulses in which case the magnet 51 is die-energized, releasing the dog 35 which, however, is now held withdrawn by the position of the pin 37 on the rocker 33.

To indicate the particular set of conductors in the selected radial group to which the wipers 118 have been moved further indicating means are provided. Numerals corresponding to the sets of conductors in the radial group are inscribed on the periphery of the driving element in a manner such that as the switch wipers are moved or stepped radially across the contacts of the bank strip selected the corresponding numeral will appear in the bracket formed by the fingers 77 on one end of the carriage 66.

Restoration of the switch is accomplished when the magnet 16 is tie-energized and its armature element 11 engages the lever 17 causing it to move the control bar 60 longitudinally. The movement of the control bar rotates the lever arm 1.11 in a counter-clockwise direction around the means 112 against the spring 116. T he disk 191 and its contact springs N2, 103, and 1M are thereby shifted through a partial. rotation as limited by the stop post 108 and the stop lug 1%7 with the result that the energization sequence of the motor magnets 41, 42 and 43 is reversed as explained hereinbefore with a resulting reversal in the direction of rotation of the motor armature 2 The mag nets 51 and 52 are now energized in that order, restraiir ing longitudinal movement of the dog 35 and withdraw ing the dog 34 from further contact with the prongs of the star wheel 25 as it now rotates counter-clockwise. As soon as the switch wipers have been fully withdrawn from the bank strip 91 with which engaged the lock bar 73 acts to lock the carriage 66 to the driving element 743, the latter element now moving the carriage 66 and its wiper assembly to their normal position against the stop 81. An instant after the contact with the stop 31 of the wiper assembly, the magnets 52 and 51 are tie-energized in that order and the arresting dog 34 is thrust into engagement with the prong of the star wheel 25 which has just cleared the tip of the dog When the driving element 7% has returned the wiper carriage do to normal the stop post 6 will have engaged the projection 6th? of the control bar 60 moving it in a clockwise direction about the pivot pin 113 and out of engagement with the lever 17 and the lever 82. Since the control bar is new free to more longitudinally, the action of the spring 116 will cause the lever arm iii to return the interrupter mechanism use to its operational position thus completing the restoration of the switch to its normal position shown in Fig. 2.

Having thus described my invention what 1 consider new and desire to protect d by Letters Patent is:

1. In a control mechanism for electric switching apparatus, a rotatable shaft, a rotatable armature having poles rigidly mounted on said shaft, electromagnet means for successively rotating a plurality of magnetic fields to rotate said armature and thereby rotate said shaft, a pinion gear rigidly mounted on said shaft, a rotatable member having gear teeth thereon, said gear teeth engaged with said pinion gear whereby the rotation of said shaft is transmitted to said rotatable member, a star wheel 11'- rigidly mounted on said shaft, afirst and a second arrestingadog, said dogs operable to engage the points of said star wheel as said shaft and said star wheel are rotated, and means for operating said arresting dogs to thereby control the rotation of said shaft whereby the rotation of said rotatable member is controlled.

.2. In a control mechanism for electric switching apparatus as claimed in claim 1, said electromagnet means comprising a plurality of electromagnets having polepieces, said pole-pieces circularly disposed with respect to said shaft, means for sequentially and momentarily energizing said electromagnets to therebycause each of said pole-pieces to be sequentially and momentarily magnetized, and means for operating said last mentioned means, said armature poles arranged on said shaft to be successively attracted to said pole-pieces as said polepieces are sequentially and momentarily magnetized to thereby cause said armature to rotate whereby said shaft is rotated.

3. In a control mechanism for electric switching apparatus as claimed in claim 1, said electromagnet means comprising a plurality of electromagnets having polepieces, said pole-pieces circularly disposed with respect to said shaft, and means operated by said shaft for successively and periodically energizing said electromagnets to thereby cause each of said pole-pieces to be successively and periodically magnetized, each of said armature poles arranged on said shaft to be attracted to each of said pole-pieces in succession as said pole-pieces are successively and periodically magnetized to thereby cause said armature to rotate thereby rotating said shaft.

4. in a control mechanism as claimed in claim 3, said means for successively and periodically energizing said electromagnets comprising a plurality of contact spring pairs, said pairs radially disposed with respect to said shaft and each of said pairs controlling an energizing circuit for each one of said electromagnets, respectively, and a cam having lobes rigidly mounted on said shaft, said lobes adapted to be moved between said springs of said contact spring pairs as said shaft is rotated to thereby cause said contact spring pairs to control said respective electromagnet energizing circuits, the rotation of said shaft thereby successively closing each of said energizing circuits to thereby periodically energize each of said electromagnets.

5. In a control mechanism as claimed in claim 4 wherein said lobes open said energizing circuits when moved between said springs of said associated contact spring pairs and close said energizing circuits when moved from between said associated contact spring pairs.

6. A control mechanism for an electric switch comprising a rotatable shaft, motor means for rotating said shaft, a rotatable member controlling the movement of said switch from a normal position, .a driving wheel rigidly mounted on said shaft, said wheel having means thereon for transmitting the rotary motion of said shaft to said rotatable member to move said switch from a normal position, a star Wheel rigidly mounted on said shaft, a first and second arresting dog, said dogs operable to alternately in n shuttle-like manner engage said star wheel as said star wheel is rotated, means for operating said arresting dogs to thereby control the rotation of said rotatable member whereby said movement of said switch is controlled, means for reversing said motor means to reverse the rotation of said shaft to thereby reverse the rotation of said rotatable member, and means for operating said last mentioned means to thereby restore said switch to said normal position.

7. A control mechanism for an electric switch comprising a rotatable shaft, means for rotating said shaft comprising a first, second, and third electromagnet, said electromagnets having pole-pieces symmetrically and radially disposed Wiii respect to said shaft, means for periodically energizing said first, second, and third electromagnets successively in that order to thereby periodically magnetize said respective pole-pieces in said order, and an armature having four poles, said armature rigidly mounted on said shaft, said poles symmetrically and radially disposed with respect to said shaft, each of said poles adapted to be successively attracted to each of said pole-pieces as said pole-pieces are periodically magnetized in said order to thereby cause said armature and said shaft to rotate in one direction, a rotatable member controlling the movcment of said switch, a drive wheel rigidly mounted on said shaft, said wheel having means thereon for transmitting the rotary motion of said shaft to said rotatable member to move said switch from a normal position as said shaft is caused to rotate in one direction, a star wheel rigidly mounted on said shaft, 21 first and second arresting dog. said dogs operable to alternately engage said star wheel as said star wheelis rotated, and means for operating said arresting dogs to thereby control the rotation of said rotatable member whereby said movement of said switch is controlled.

8. A control mechanism as claimed in claim 7, said means for periodically energizing said electromagnets comprising said rotatable shaft, a first, second, and third pair of spring contacts to control the energizing circuits of said first, second, and third electromagnets, respectively, said pairs symmetrically and radially disposed with respect to said shaft, a cam having four lobes rigidly mounted on said shaft, said lobes adapted to be successively moved between said springs of said spring contact pairs as said cam is rotated, said lobes opening said associated energizing circuits when moved between said springs and closing said associated circuits when moved from between said springs, said lobes so arranged on said cam with respect to said spring pairs that only one of said energizing circuits is closed at any rotational position of said cam, the rotation of said shaft causing said cam lobes to successively and periodically close said energizing circuits to thereby successively and periodically energize said first, second, and third electromagnets in that order.

9. A control mechanism as claimed in claim 8, reversing means to cause said energizing means to periodically energize said electromagnets in the reverse of said order to thereby periodically magnetize said respective polepieces in the'reverse of said order, said magnetizing of said pole-pieces in said reverse of said order causing said armature and said shaft to be rotated in the opposite direction whereby the rotation of said rotatable menn her is reversed, and means for operating said last mentioned means to thereby restore said switch to said normal position.

10. A control mechanism as claimed in claim 8, said reversing means comprising a movable mounting carrying said first, second, and third spring contact pairs, said mounting pivoted centrally about said shaft in response to said operating means to turn said spring contact pairs in the direction of rotation of said shaft a predetermined angular amount, said turn shifting the instantaneous relation of said cam lobes and said spring pairs to thereby open the energizing circuit of the one electromagnct whose pole-piece at the instant attracts one of said armature poles and reclose the energizing circuit of the one electromagnet whose pole-piece the said armature pole last passed thereby re-attracting said armature pole to said last-mentioned pole-piece to thereby cause the rotation of said armature to be reversed, said shaft and said cam being thereby caused to rotate in the reverse direction whereby said electromagnets are energized in said reverse of said order.

11. In a control mechanism for an electric switch having a rotatable driving means, a motor means for rotating said driving means, a star wheel coupled to said driving means, said star wheel controlling the rotation of said driving means, a pair of arresting dogs engageable with said star wheel, a rocker, means for pivotally v connecting said arresting dogs to opposite ends of said rocker, magnet means for operating said rocker to thereby cause said arresting dogs to be alternately introduced into, and withdrawn from, engagement with said star wheel to thereby cause the rotation of said star wheel and, thereby, the rotation of said rotatable driving means to be periodically interrupted, and means for withholding both of said arresting dogs from engagement with said star wheel to thereby permit said star wheel and thereby said rotatable driving means to be continuously rotated.

12. In a control mechanism for an electric switch adapted for step-by-step operation, a rotatable member controlling the movement of said switch, motor means for directly rotating said member, a star wheel coupled to said rotatable member, said star wheel having a plurality of points for controlling the rotation of said member, a first and second arresting dog, a rocker pivoted substantially centrally, means for pivotally connecting said arresting dogs to opposite ends of said rocker with said dogs adapted to be engaged with the points of said star wheel, means for pivoting said rocker to cause said first and said second arresting dogs to alternately engage the points of said star wheel thereby periodically arresting the rotation of said star wheel, and a first operating magnet for controlling said pivoting means, said magnet actuated to withdraw said first arresting dog from engagement with a point of said star wheel and to introduce said second arresting dog with a next succeeding point as said star wheel is permitted to rotate and said magnet restored to introduce said first arresting dog into engagement with said last mentioned point and to withdraw said second arresting dog from engagement with said last mentioned point whereby said star wheel is permitted to rotate a predetermined amount to thereby permit said rotatable member to rotate a predetermined amount to move said switch one step.

13. In a control mechanism as claimed in claim 12, means for locking one of said arresting dogs from engagement with said star wheel, a second operating magnet to operate said last mentioned means, actuation of said magnet operating said locking means to thereby permit said star wheel to be freely rotated as said first operating magnet is actuated thereby withdrawing the other of said arresting dogs from engagement with said star wheel whereby said rotatable member is permitted to be freely rotated to thereby move said switch in a continuous motion.

14. In a control mechanism for controlling the movements of an electric switch having a movable member, an arresting device comprising a star wheel coupled to said member and controlling the movement thereof, means for rotating said star wheel, a first and a second arresting dog, said first arresting dog normally engaging a point of said star wheel thereby detaining said star wheel, means for causing said dogs alternately to engage the points of said star wheel, a first electromagnet to operate said last mentioned means, said first electromagnet alternately energized and de-energized to cause said arresting dogs to be alternately withdrawn from and engaged with the points of said star wheel whereby said star wheel is permitted to advance in a step-by-step rotation to thereby cause said member to be moved in a step'by-step motion, locking means to hold said second arresting dog out of engagement with said star wheel, and a second electromagnet for operating said locking means, said second and said first electromagnet held energized to hold said second and said first arresting dog, respectively, out of engagement with said star wheel to thereby permit said star wheel to be freely rotated whereby said member is caused to move in a continuous motion.

15. In a control mechanism for a two motion selective switch having wipers, a movable member having gear teeth thereon for controlling the movement of said switch, movement of said member a first selected amount causing said switch to be moved in one direction and movement of said member a further selected amount causing said switch to be moved in a second direction, reversal of said movement of said member restoring said switch, and means for changing the direction of movement of said switch; a pinion engaged with said gear teeth of said movable member for driving said member, motor means for rotating said pinion, a star wheel coupled to said pinion for controlling the rotation thereof, a pair of arresting dogs engageable with said star wheel, one of said dogs normally detaining said star wheel, means including a first operating magnet for operating said arresting dogs, said first magnet alternately energized and de-energized to cause said arresting dogs to alternately release and detain said star wheel whereby said motor means is permitted to periodically rotate said pinion, the periodic rotation of said pinion causing said movable member to step said switch in said first direction, said direction changing means checking said movement of said switch after said switch has been moved a selected amount in said first direction and causing said switch to he stepped in said second direction a selected amount as said movement of said movable member is continued by said periodically rotating pinion, means including said first operating magnet and a second operating magnet for permitting the free rotation of said star wheel, said first and said second operating magnets held energized to hold said arresting dogs out of engagement with said star wheel, and motor reversing means controlled by said direction changing means for reversing the direction of rotation of said pinion as said last mentioned means is operated to permit the continuous rotation of said star wheel to thereby reverse the movement of said movable member to thereby restore said switch in a continuous motion.

16. In a control mechanism as claimed in claim 15, said first operating magnet and said second operating magnet adapted to be held energized at any predetermined position of said switch to thereafter permit said switch to be moved in a continuous forward direction as said movable member is freely driven by said pinion.

References Cited in the file of this patent UNITED STATES PATENTS 1,291,978 McQuarrie Jan. 21, 1919 1,460,913 Lienzen et al. July 3, 1923 2,052,059 Sengebusch Aug. 25, 1936 2,302,218 Hickey Nov. 17, 1942 2,623,126 Graybill et a1. Dec. 23, 1952 2,640,882 Kruithof June 2, 1953 2,640,884 Kruithof June 2, 1953 2,684,408 Sengebusch July 20, 1954 2,721,904 Souter Oct. 25, 1955 2,780,675 Sengebusch Feb. 17, 1957 FOREIGN PATENTS 85,768 Sweden Aug. 16, 1934 

